The two old friends were discussing their marriages. After so many years, the first man said, he still loved his wife, and he supposed his friend loved his.

The second man paused and thought a moment. “You know, I believe it’s something beyond ‘love’ in the conventional sense. A husband and wife who have been together a long time experience a bonding that makes them like the two halves of a psychological and spiritual whole. Neither is quite complete without the other. That’s when you really start to understand what Jesus meant when he said husbands and wives become ‘two in one flesh.’”

His friend agreed.

The virtue of chastity, cherished as an ideal and practiced through thick and thin, is a necessary part of marriage as these two men had lived it. That’s a hard saying for lots of people at a time when chastity is widely ignored — and mocked when it isn’t ignored. Thanks largely to the worldview promoted in the media, few elements of the Christian tradition are today probably less understood and accepted than chastity. It’s a terrible loss.

Sin of lust

Sins against chastity are hardly new, of course. The vice most obviously opposed — lust — has been around since Adam and Eve. Dante’s treatment of lust in his great poem of the late Middle Ages, “The Divine Comedy,” is a literary landmark on this subject. He situates lustful sinners in the first circle of hell, where fierce winds blow them to and fro.

Like as the starlings wheel in the wintry season

In wide and clustering flocks wing-borne, wind-borne

Even so they go, the souls who did this treason.

Hither and thither, and up and down, outworn,

Hopeless of any rest …

Author and Dante translator Dorothy Sayers explained the striking symbolism: “As [the lustful] drifted into self-indulgence and were carried away by their passions, so now they drift forever. The bright, voluptuous sin is now seen as it is — a howling darkness of helpless discomfort.”

Following biblical guidelines is the best way to strengthen marriage. Shutterstock

But if lust isn’t new, the self-conscious, ideology-driven assault on chastity now under way is. There’s something about chastity that the secularized modern mind finds deeply offensive — and this offensive something, one suspects, is self-control in sexual matters.

A while back, I asked one of my daughters why so many people get downright nasty about the Catholic Church when speaking of its views on sexual morality. Being a tough-minded realist, she said, “Guilt.”

It stands to reason. The sexual revolution that erupted in the 1960s was marketed as liberation — throwing off the repressions and restraints of the ancient Puritan code that supposedly ruled people’s lives before then.

Unfortunately, as we’ve learned to our regret, abandoning self-control in sex has been anything but liberating. For many people, sex has become an obsession, sometimes an addiction, as one sees in the unhappy experience of men who’ve become hooked on Internet pornography at the cost of their self-respect and their relationships with their wives.

Decline of marriage

Note, too, that while the technology of this Web-based addiction is new, the addiction itself isn’t. St. Augustine, no stranger to sexual addiction in his youth, wrote in his “Confessions,” “When lust is pandered to, a habit is formed; when habit is not checked, it hardens into compulsion. These were like interlinking rings forming what I have described as a chain … .”

Rejecting chastity hurts not only individuals but society. In particular, its destructive impact on the institution of marriage is clear.

That marriage is in trouble in the United States and countries like it can hardly be doubted. Marriages in America fell from 2.44 million in 1990 to 2.08 million in 2009, while the population was rising by 60 million. As of 2011, just 51 percent of Americans were married compared with 57 percent in 2000.

Things are no better in the Catholic sector.

Back in 1990, with American Catholics numbering 55 million, there were 334,000 Catholic marriages. By 2010, when the Catholic population had jumped to 68.5 million, Catholic marriages had fallen by nearly half, to 179,000.

Of course many factors contribute to the marriage decline. Reducing it all to contraception and the contraceptive mentality would overstate the case. Easy divorce and economic pressures are part of the picture, as are ongoing efforts to sell Americans on same-sex marriage, which robs traditional man-woman marriage of the unique place it’s always occupied up to now in the life of society.

But alongside factors like these, the campaign against chastity has had a crucial role in the undermining of marriage.

Some people avoid marriage because of the restrictions it imposes on sexual activity, while others, having married, find those restrictions distasteful and, claiming an unconditional right to sexual fulfillment, abandon spouses (and often children) and divorce.

Chastity is the realistic antidote to all this. St. Thomas Aquinas, reflecting on it, makes the point that this virtue is fundamental to “self-possession” in sexual matters, whereas unchastity weakens and destroys it. Philosopher Josef Pieper, contrasting self-possession with its opposite, writes: “An unchaste man wants above all something for himself. … Unchastity … is selfishly intent upon the ‘prize,’ upon the reward of illicit lust.”

Selfish, self-interested, deadly cold: here’s the heart of unchastity and lust. But the virtue of chastity preserves that openness to the other in self-giving love that stands at the heart of healthy relationships, above all marriage.

The chaste man or woman possesses the necessary freedom to make the gift of self that is part of, but by no means limited to, the loving sexual encounter of husband and wife.

Pope Benedict XVI in his encyclical Deus Caritas Est (“God is Love”) goes so far as to extend the reach of chastity to the relationship with God. “Love … is a journey,” he wrote, “an ongoing exodus out of the closed inward-looking self toward its liberation through self-giving, and thus toward authentic self-discovery and indeed the discovery of God.”

Seeking real chastity

Chastity also is necessary to a healthy spiritual life.

St. Josemaría Escrivá, founder of Opus Dei, places his discussion of chastity — “holy purity,” he calls it — near the start of his guide book to sanctity, “The Way.” There’s no mystery about that: Progress in the interior life is nearly impossible unless a person sets out seriously to acquire chastity, since that’s the only way to break the chain of compulsive self-seeking forged by a habit of unchastity.

How to go about it?

Grace is indispensable, and God will give the grace of chastity to those who truly want it. But that really wanting it is essential. Much as God wishes to give this gift, his respect for human freedom won’t allow him to do that unless we want it.

The sincere desire for chastity requires much more than simply saying now and then, “Wouldn’t it be nice … ?”

There are things we can and must do for ourselves.

Prayer and mortification — saying an occasional no to some small thing like a dessert or a merely self-indulgent nap — are both required. Prayer keeps us in touch with God. Mortification is practice in the self-discipline required to resist temptations to instant gratification.

Frequent and regular use of the sacrament of Penance also is an obvious necessity. And for those who suffer from sexual addiction or something like it, professional help from a counselor who understands the importance of chastity may be required.

These days, too, people who are serious about this virtue may have to separate themselves in whole or part from the popular culture, either sharply limiting their intake or, if necessary, eliminating exposure to it almost entirely from their lives.

Face it, a man who routinely settles down in the evening to some beer and watch whatever turns up on TV is inviting trouble for himself. So is someone who mindlessly surfs the Internet, scanning whatever happens to catch his fancy. Do people like these truly want to be chaste?

Probably not. For them, chastity is wishful thinking at best: “Wouldn’t it be nice … ?”

The rewards of chastity are enormous.

Self-possession and self-control. The capacity to give oneself to another in disinterested, selfless love. The possibility of enjoying a happy and fruitful marriage as God wants marriage to be. And finally the fulfillment of all relationships and all loves in everlasting life with God.

Not a bad deal.

Russell Shaw is an OSV contributing editor. This is the fourth part of a monthly Year of Faith series on virtues.